Uridine Product Number U 3750 Store at Room Temperature Product Description Precautions and Disclaimer For Laboratory Use Only. Not for drug, household or Molecular Formula: C9H12N2O6 other uses. Molecular Weight: 244.2 CAS Number: 58-96-8 Preparation Instructions Melting Point: 165 °C This product is soluble in water (50 mg/ml), yielding a 1 λmax: 205 nm, 261 nm (pH 7.3) clear, colorless solution. Extinction Coefficient: EmM = 9.8 (205 nm), 10.1 1 (261 nm) (pH 7.3) Storage/Stability Specific Rotation: +4 °(20 mg/ml, H2O) Stock solutions of uridine in water at pH 7 are Melting Point: 165 °C expected to be stable for several days when stored at ° pKa: 9.3; 12.6 4 C. Synonyms: 1-β-D-ribofuranosyluracil; uracil- 1-β-D-ribofuranoside; uracil riboside References 1. The Merck Index, 12th ed., Entry# 10016. Uridine is the ribonucleoside of the pyrimidine base 2. Nucleic Acids in Chemistry and Biology, 2nd ed., uracil, which is one of the four bases found in Blackburn, G. M., and Gait, M. J., eds., Oxford ribonucleic acid (RNA). The monophosphate form of University Press (Oxford, UK: 1996), pp. 46-48. uridine (UMP) is formed from orotate via the 3. Oxford Handbook of Nucleic Acid Structure, intermediate orotidylate.2 Structural analyses of Neidle, S., ed., Oxford University Press (Oxford, uridine:cytosine (U:C) RNA base pairs in the solid UK: 1999), pp. 546, 574. state and uridine:guanine (U:G) base pairs in the 4. Simpson, L., et al., Uridine insertion/deletion RNA solution state have been discussed.3 A review of editing in trypanosome mitochondria: a complex uridine insertion and deletion in RNA editing in business. RNA, 9(3), 265-276 (2003). trypanosome mitochondria has been published.4 5. Seyfang, A., and Landfear, S. M., Substrate depletion upregulates uptake of myo-inositol, The uptake of uridine in adenosine-depleted cells in glucose and adenosine in Leishmania. Mol. various Leishmania strains has been studied.5 A study Biochem. Parasitol., 104(1), 121-130 (1999). of cultured LLC-PK1 cells to examine gadd153 mRNA 6. Huang, Q., et al., Induction of gadd153 mRNA by expression has utilized uridine at 25 mM.6 The nutrient deprivation is overcome by glutamine. identification of uridine in culture supernatants from Biochem. J., 341(Pt 1), 225-231 (1999). Streptomyces citricolor by high-resolution NMR and 7. Abel, C. B., et al., Characterization of metabolites by directly coupled HPLC-NMR methods has been in intact Streptomyces citricolor culture described.7 supernatants using high-resolution nuclear magnetic resonance and directly coupled high- pressure liquid chromatography-nuclear magnetic resonance spectroscopy. Anal. Biochem., 270(2), 220-230 (1999). Sigma brand products are sold through Sigma-Aldrich, Inc. Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side of the invoice or packing slip. GCY/NSB 1/04 .